1. Field of the Invention
The present invention relates to a ligative suturer, and more specifically, it relates to the structure of a ligative suturer which is employed for an endoscopic surgical operation.
2. Description of the Background Art
In general, an operation for surgically treating biliary calculus or pneumothorax is adapted to laparotomically incise a human body from the epigastrium to a portion around the umbilicus. However, such laparotomy results in a large wound, leading to a severe postoperative pain and requirement for hospitalization for 2 to 3 weeks. Further, the patient is forbidden to exercise hard for about 3 months after discharge.
In order to solve these problems, therefore, an endoscopic surgical operation is employed in recent years.
With reference to FIG. 29, such an endoscopic surgical operation is now described. In order to treat pneumothorax 403 which originates from a lung 402, for example, carbon dioxide (CO.sub.2) is intraperitoneally supplied through a chest wall 400, to bring an abdominal cavity 401 into a positive pressure state. Thereafter the chest wall 400 is pushed up from its interior. Thus, a space which is necessary for the endoscopic surgical operation can be ensured.
Then, prescribed appliances called trocars 500 are passed through prescribed positions of the chest wall 400 to insert a celioscope 600, a forceps 6 and a ligative suturer 1 through the trocars 500, for carrying out the operation while projecting an image obtained from the celioscope 600 on a monitor (see FIG. 30).
When a patient 410 undergoes an abdominal operation, a wound 411 is formed between the epigastrium and a portion around the umbilicus, as shown in FIG. 31. If the patient 410 alternatively undergoes the aforementioned endoscopic surgical operation, however, only holes 412A to 412D are formed for inserting the trocars 500, as shown in FIG. 32.
Consequently, only hospitalization for 3 to 7 days is required, and the patient can orally ingest food from the day following the operation and gets better soon. Thus, the burden on the patient can be eased.
A ligation apparatus for ligating blood vessels which is employed for the endoscopic surgical operation is now described with reference to FIGS. 33 to 36, on the basis of a technique disclosed in Japanese Patent Laying-Open No. 7-51274 (1995).
In this ligation apparatus, a notched surface 1a is formed on a forward end of a rod 1 which consists of a metal rod having a diameter of about 4 mm or the like. A relatively heavy pillow-shaped movable body 2 is placed on the notched surface 1a.
The movable body 2 is movably held by the notched surface 1a and a cover 3, while defining a space which is substantially similar to the diameter of a ligature 5. The cover 3 is fixed to the rod 1 by a screw 7. An angular thread guard 4 is formed on a prescribed position of the upper surface of the cover 3.
Further, the cover 3 is provided on its forward end with a ligature guide surface 3A consisting of a first slope 3 which is gradually inclined from the forward end toward the interior and a second slope 3e which downwardly extends to form a sharp angle with the first slope 3a. A notched groove 3b is formed on the ligature guide surface 3A.
The movable body 2 has a trunk part 2c and a tapered end 2a which is provided on the forward end of the body part 2c. The tapered end 2a is provided on its forward end with a hole 2b for fastening the ligature 5. On the other hand, a notched groove 1b is formed on the forward end of the notched surface 1a.
The movable body 2 is supported by the notched surface 1a and the cover 3 so that the tapered end 2a forwardly protrudes from the notched grooves 3b and 1b which are formed in the central forward end of the ligature guide surface 3a and the forward end of the notched surface 1a respectively, as shown in FIGS. 35 and 36.
The movable body 2 is movably held in a space which is defined by the notched surface 1a and the cover 3, not to jut out from this space. This movable body 2 is so sized that the same has a clearance which is similar to the diameter of the ligature 5 in the space enclosed with the notched surface 1a, the cover 3 and both side edges 3c of the cover 3 and is slightly moved following movement of the ligature 5.
A state of employment of the ligation appratus having the aforementioned structure is now described with reference to FIGS. 37 to 58 and FIGS. 59 to 66. FIGS. 59 to 66 are model diagrams for illustrating ligation in the ligation appratus.
Referring to FIG. 37, a second end of the ligature 5 whose first end is fastened to the tapered end 2a of the movable body 2 of the ligation apparatus is passed through the rear side of a blood vessel 10, so that this second end is grasped by a forceps 6. This state corresponds to that shown in FIG. 59.
Referring to FIG. 38, the ligature 5 is hung on the thread guard 4 which is provided on the upper side of the ligation apparatus, and bent along the blood vessel 10, to form an elongated ring. This state corresponds to that shown in FIG. 60.
Referring to FIG. 39, the ligature 5 is guided along the side edge of the cover 3 and slid on the ligature guide surface 3A, so that its intermediate portion is introduced into the interior of the cover 3 from the upper surface of the tapered end 2a of the movable body 2, as shown in FIG. 40. This state corresponds to that shown in FIG. 61.
Referring to FIGS. 41 to 45, the ligature 5 is moved in the space between the inner surface of the cover 3 and the upper surface of the movable body 2 and slid along the upper surface of the movable body 2, to be positioned on the notched surface 1a on the rear portion of the movable body 2. In the aforementioned respective operations, the tapered end 2a of the movable body 2 is supported by the notched grooves 3b and 1b of the cover 3 and the notched surface 1a, while the movement of the rear side of the movable body 2 is limited on the inner surface of the side edge 3c of the cover 3. Thus, the movable body 2 inhibited from falling or the like. This state corresponds to that shown in FIG. 62.
Referring to FIGS. 46 to 49, the ligature 5 is advanced by the forceps 6 while being slid between the upper surface of the notched surface 1a and the lower surface of the movable body 2. This state corresponds to that shown in FIG. 63.
Referring to FIG. 50, the ligature 5 is pulled out from the notched surface 1a, to be released from the thread guard 4. This state corresponds to that shown in FIG. 64. Thereafter the ligature 5 is pulled out from the notched surface 1a by the forceps 6, thereby forming a loop 5b having a twisted portion 5a defining a knot as shown in FIG. 51. This state corresponds to that shown in FIG. 65.
Referring to FIGS. 52 and 53, the ligature 5 is pulled along arrow to reduce the loop 5b, thereby forming a single knot 5c binding a portion around an affected part 10. This state corresponds to that shown in FIG. 66.
In order to prevent the single knot 5c from getting loose, the second end of the ligature 5 is returned by the forceps 6 so that the ligature 5 is hung on the thread guard 4 again for forming an elongated ring similarly to the above, thereby forming a new knot on the single knot 5c through a process similar to the above, as shown in FIGS. 54 to 58. Thus, a ligation part 5b is formed by a double knot which is not readily untied by external force.
Consequently, it is possible to readily ligate the blood vessel 10 in the abdominal cavity while observing a monitor, due to the ligation apparatus having the movable body 2 which is provided on the forward end of the rod 1.
In the aforementioned ligation apparatus, however, the thread guard 4 regularly protrudes from the upper surface of the cover 3. Therefore, it is rather difficult for the operator to release the ligature 5 from the thread guard 4 in the narrow abdominal cavity (see FIGS. 49 and 50). When the ligation apparatus is introduced into/discharged from the abdominal cavity with a trocar, further, the thread guard 4 may hang on the trocar to break the same.
According to the structure of the aforementioned ligation apparatus, further, the first end of the ligature 5 must be previously connected to the tapered end 2a of the movable body 2. Thus, the aforementioned ligation apparatus cannot be applied to an operation for blocking pneumothorax with an operative thread having needles mounted on both ends thereof.